CHQ-MRC2/DIN(SCI) Mains Relay Controller DIN Enclosure with SCICHQ MRC2 DIN(SCI) Mains Relay Controller DIN Enclosure with SCI Manufactured by Hochiki, this Hochiki CHQ MRC2 DIN (SCI) Mains Relay Controller DIN Enclosure With SCI is a Single Input Output Module, which provides a single, mains rated relay output for the control of such devices as dampers, extractors or plant and equipment shutdown. The monitored input can be used for local power supply fault monitoring or as a general purpose input. The unit is